Hacker News Reader

Comment by eviks | Hacker News Reader

Excellent technical presentation! Though the style itself is a bit too "clay-like", like I wouldn't expect a cube melding with the terrain sand to be a smooth glued connection. Is that some "inherent" SDF thing or just a style of the demo?

View on HN

I think it is an artifact of the optimizations he uses and while it's artistically limiting, I think a right game with the right visual language could make this work to its advantage in terms of uniqueness/distinctiveness. It's a one trick pony if not avoidable though.

Basically it's the result of a smoothing function that blends the sampled SDF value of the two nearest bodies. You can simply pick the minimum SDF value and get no blending at all.

> You can simply pick the minimum SDF value and get no blending at all.

While this true for traditional SDF rendering (e.g. raymarching), the method of "interpolating cached distances" used here means that you will always get blending between objects.

Oh right, of course. I wasn’t thinking about the specific implementation in the video. Thanks.

I believe you can do regular hard edged intersections. You can see in his operator list some are listed as “smoothSubtract” and some are just “subtract”

It’s just easy to do the melding thing with SDFs so a lot of people do it

From his description of the approach I suspect its also to smooth over sharp edges that the grid optimization doesn't like so much.

Reply on news.ycombinator.com